diff --git a/openjiuwen/core/sys_operation/cwd.py b/openjiuwen/core/sys_operation/cwd.py
index bee5e411f..bbd5c05e4 100644
--- a/openjiuwen/core/sys_operation/cwd.py
+++ b/openjiuwen/core/sys_operation/cwd.py
@@ -144,6 +144,21 @@ def set_workspace(path: str) -> None:
     _state().workspace = _resolve(path)
 
 
+def get_agent_history_base_dir() -> str:
+    """Base directory for per-session tool history (``.agent_history/``).
+
+    Prefers the agent workspace; when none is configured, falls back to a
+    user-level directory (``~/.openjiuwen/agent_history``) instead of the
+    project CWD, so history files never pollute the user's project tree
+    (#1490).
+    """
+    workspace = get_workspace()
+    if workspace:
+        return workspace
+    home = os.path.expanduser("~")
+    return os.path.join(home, ".openjiuwen", "agent_history")
+
+
 # ---- Team workspace: shared across team members ---------------------------
 
 def get_team_workspace() -> str | None:
diff --git a/openjiuwen/harness/tools/filesystem.py b/openjiuwen/harness/tools/filesystem.py
index 80c7b2ac4..969016adf 100644
--- a/openjiuwen/harness/tools/filesystem.py
+++ b/openjiuwen/harness/tools/filesystem.py
@@ -24,7 +24,7 @@
 from openjiuwen.core.common.logging import logger
 from openjiuwen.core.foundation.tool.base import Tool
 from openjiuwen.core.sys_operation import SysOperation
-from openjiuwen.core.sys_operation.cwd import get_cwd, get_workspace
+from openjiuwen.core.sys_operation.cwd import get_agent_history_base_dir, get_cwd, get_workspace
 from openjiuwen.harness.prompts.tools import build_tool_card
 from openjiuwen.harness.tools.base_tool import ToolOutput
 
@@ -904,7 +904,7 @@ def _detect_encoding(raw: bytes) -> str:
         return "utf-16-le" if raw[:2] == b"\xff\xfe" else "utf-8"
 
     def _build_history_path(self, session: Any) -> str:
-        base_dir = get_workspace() or str(pathlib.Path(get_cwd()).expanduser().resolve())
+        base_dir = get_agent_history_base_dir()
         agent_id = (
             session.agent_id() if hasattr(session, "agent_id")
             else session.get_agent_id() if hasattr(session, "get_agent_id")
@@ -1221,7 +1221,7 @@ def _try_quote_variants(self, content: str, old_str: str) -> Optional[str]:
         return content[index:index + len(old_str)]
 
     def _build_history_path(self, session: Any) -> str:
-        base_dir = get_workspace() or str(pathlib.Path(get_cwd()).expanduser().resolve())
+        base_dir = get_agent_history_base_dir()
         agent_id = (
             session.agent_id() if hasattr(session, "agent_id")
             else session.get_agent_id() if hasattr(session, "get_agent_id")
diff --git a/openjiuwen/harness/tools/shell/bash/_tool.py b/openjiuwen/harness/tools/shell/bash/_tool.py
index 717a2a009..eb4f7c725 100644
--- a/openjiuwen/harness/tools/shell/bash/_tool.py
+++ b/openjiuwen/harness/tools/shell/bash/_tool.py
@@ -149,8 +149,8 @@ def _parse_inputs(inputs: Dict[str, Any]) -> _BashInputs:
     # ── invoke ────────────────────────────────────────────────
 
     def _build_history_path(self, session: Any) -> str:
-        from openjiuwen.core.sys_operation.cwd import get_cwd, get_workspace
-        base_dir = get_workspace() or str(pathlib.Path(get_cwd()).expanduser().resolve())
+        from openjiuwen.core.sys_operation.cwd import get_agent_history_base_dir
+        base_dir = get_agent_history_base_dir()
         agent_id = (
             session.agent_id() if hasattr(session, "agent_id")
             else session.get_agent_id() if hasattr(session, "get_agent_id")
diff --git a/openjiuwen/harness/tools/shell/powershell/_tool.py b/openjiuwen/harness/tools/shell/powershell/_tool.py
index e7018f20c..159c127bd 100644
--- a/openjiuwen/harness/tools/shell/powershell/_tool.py
+++ b/openjiuwen/harness/tools/shell/powershell/_tool.py
@@ -125,8 +125,8 @@ def _parse_inputs(inputs: Dict[str, Any]) -> _PowerShellInputs:
         )
 
     def _build_history_path(self, session: Any) -> str:
-        from openjiuwen.core.sys_operation.cwd import get_cwd, get_workspace
-        base_dir = get_workspace() or str(pathlib.Path(get_cwd()).expanduser().resolve())
+        from openjiuwen.core.sys_operation.cwd import get_agent_history_base_dir
+        base_dir = get_agent_history_base_dir()
         return os.path.join(
             base_dir, ".agent_history",
             f"file_ops_{self._agent_id}_{session.get_session_id()}.json",
diff --git a/tests/unit_tests/core/sys_operation/test_cwd.py b/tests/unit_tests/core/sys_operation/test_cwd.py
new file mode 100644
index 000000000..5bab6bd5d
--- /dev/null
+++ b/tests/unit_tests/core/sys_operation/test_cwd.py
@@ -0,0 +1,42 @@
+# coding: utf-8
+# Copyright (c) Huawei Technologies Co., Ltd. 2026. All rights reserved.
+
+"""Unit tests for the per-agent CWD state helpers in cwd.py.
+
+Focus: ``get_agent_history_base_dir`` — the tool-history base directory
+that must prefer the agent workspace and, when none is configured, fall
+back to a user-level directory instead of the project CWD (#1490).
+"""
+
+import os
+import tempfile
+
+from openjiuwen.core.sys_operation.cwd import (
+    get_agent_history_base_dir,
+    init_cwd,
+    set_workspace,
+)
+
+
+def _reset_cwd_state() -> None:
+    """Reinitialize the per-context CWD state without a workspace."""
+    init_cwd(os.getcwd())
+
+
+class TestGetAgentHistoryBaseDir:
+    def test_returns_workspace_when_set(self):
+        workspace = tempfile.mkdtemp()
+        try:
+            set_workspace(workspace)
+            assert get_agent_history_base_dir() == os.path.realpath(workspace)
+        finally:
+            _reset_cwd_state()
+
+    def test_falls_back_to_user_level_dir_when_workspace_unset(self):
+        _reset_cwd_state()
+        base = get_agent_history_base_dir()
+        assert ".openjiuwen" in base
+        assert "agent_history" in base
+        assert not base.startswith(os.getcwd()), (
+            "history base must NOT be the project CWD (#1490)"
+        )